DEVICE GUIDE
How to check an LCD screen
Separate edge bleed, clouding, viewing-angle glow and normal panel variation.
Updated September 1, 2026 · 5 minute read
Before you begin
These are visual browser checks, not manufacturer certification, professional calibration or repair diagnosis.
A focused five-step check
- 01
Warm the panel and disable dynamic contrast.
- 02
Use black in a dark room at normal brightness.
- 03
Move your head slightly: angle-dependent glow is different from a fixed patch.
- 04
Inspect 5%, 10% and 50% grey for uniformity.
- 05
Check near-black and near-white contrast steps.
GOOD TO KNOW
Phone-camera exposure can greatly exaggerate black-screen artifacts. Judge primarily with your eyes.